Question

Trace the movement of an ion from the soil to the center of a root, listing all tissues through which the ion must pass. Describe the function of each tissue.

Answer 1

Ion absorption by plant root is determined by both root physiology and the mobility of ion in the soil itself. There are 3 process by which the movement of ions in the soil amd plant root uptake namely,

Mass flow- movement of diffused ions in the soil to take up by the roots can be by the upward/ downward movement occurring int the soil through its pores.

Diffusion is the process by which the mo3of ions by the driving force being the ion concentration gradient, always from higher concentration to the lower concentration.

Root interception occurs due to growth of roots through the soil that increases surface area contact with the soil particles, increasing greater chance for ion absorption.

Tissues involving in the movement of ion process

Plant tissues are of two types in pericycle of vascular tissues that is pholem and xylem were pholem carries product of photosynthesis from leaves to the roots, Xylem plays role in take up of water and mineral ions from the root to the other parts of the plant.

Root hair cells are of cell wall and cell memberane through which the water and mineral ions first enters by osmosis. These cells have large vacuoles that allows to store water and mineral salts.

Thua from root hair cells water and mineral salts moves across the parenchymal cells of the cortex in two major ways, namely by osmosis amd by simple diffusion. The water pass through endodermis to the xylem ten xylem pass through it to the stem.

From the soil water, the water enters root hairs by osmosis.

Water crosses root cortex by osmosis and diffusion.